diff --git a/CHANGELOG.md b/CHANGELOG.md
index a8ee4e7..755c23b 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -5,6 +5,12 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/).
 
 ## [Unreleased]
 
+## Changed
+- DiscreteTune.__call__ will now always return a numpy.ndarray object, regardless of argument type
+
+## Fixed
+- fixed bug where DiscreteTune did not respect order of identifiers when called with an array
+
 ## [0.5.1]
 
 ### Added
diff --git a/attune/_discrete_tune.py b/attune/_discrete_tune.py
index 52ae447..74cb650 100644
--- a/attune/_discrete_tune.py
+++ b/attune/_discrete_tune.py
@@ -35,7 +35,7 @@ def __init__(
     def __repr__(self):
         return f"DiscreteTune({repr(self.ranges)}, {repr(self.default)})"
 
-    def __call__(self, ind_value, *, ind_units=None):
+    def __call__(self, ind_value, *, ind_units=None) -> np.ndarray:
         """Evaluate the DiscreteTune at specific independent value(s).
 
         Paramters
@@ -54,20 +54,16 @@ def __call__(self, ind_value, *, ind_units=None):
         """
         if ind_units is not None and self._ind_units is not None:
             ind_value = wt.units.convert(ind_value, ind_units, self._ind_units)
-        if isinstance(ind_value, np.ndarray):
-            out = np.full(
-                ind_value.shape,
-                self.default,
-                dtype=f"U{max([len(s) for s in self.ranges.keys()])}",
-            )
-            for key, (imin, imax) in self.ranges.items():
-                out[(ind_value >= imin) & (ind_value <= imax)] = key
-            return out
-        else:
-            for key, (imin, imax) in self.ranges.items():
-                if imin <= ind_value <= imax:
-                    return key
-            return self.default
+        ind_value = np.asarray(ind_value)
+        out = np.full(
+            ind_value.shape,
+            self.default,
+            dtype=f"U{max([len(s) for s in self.ranges.keys()])}",
+        )
+        # work in reverse so that the first valid entry persists
+        for key, (imin, imax) in reversed(self.ranges.items()):
+            out[(ind_value >= imin) & (ind_value <= imax)] = key
+        return out
 
     def __eq__(self, other):
         return self.ranges == other.ranges and self.default == other.default
diff --git a/attune/_tune.py b/attune/_tune.py
index 6b4128e..4b2a5ad 100644
--- a/attune/_tune.py
+++ b/attune/_tune.py
@@ -55,7 +55,7 @@ def __repr__(self):
             return f"Tune({repr(self.independent)}, {repr(self.dependent)})"
         return f"Tune({repr(self.independent)}, {repr(self.dependent)}, dep_units={repr(self.dep_units)})"
 
-    def __call__(self, ind_value, *, ind_units=None, dep_units=None):
+    def __call__(self, ind_value, *, ind_units=None, dep_units=None) -> np.ndarray:
         if ind_units is not None and self._ind_units is not None:
             ind_value = wt.units.convert(ind_value, ind_units, self._ind_units)
         ret = self._interp(ind_value)
diff --git a/docs/structure.rst b/docs/structure.rst
index 3b43428..c4cdd7a 100644
--- a/docs/structure.rst
+++ b/docs/structure.rst
@@ -78,15 +78,15 @@ You can, however, place higher priority (earlier) ranges inside of other ranges
 .. code-block:: python
    
    dt = attune.DiscreteTune({"hi": (100, 200), "lo": (10, 20), "inner": (50, 60), "med": (20, 100)}, default="def")
-   dt(5) == "def"
-   dt(15) == "lo"
-   dt(20) == "lo"
-   dt(30) == "med"
-   dt(55) == "inner"
-   dt(70) == "med"
-   dt(100) == "hi"
-   dt(150) == "hi"
-   dt(500) == "def"
+   dt(5) == np.array("def")
+   dt(15) == np.array("lo")
+   dt(20) == np.array("lo")
+   dt(30) == np.array("med")
+   dt(55) == np.array("inner")
+   dt(70) == np.array("med")
+   dt(100) == np.array("hi")
+   dt(150) == np.array("hi")
+   dt(500) == np.array("def")
 
 
 
diff --git a/tests/discrete_tune.py b/tests/discrete_tune.py
index 042d3e0..1d6bff7 100644
--- a/tests/discrete_tune.py
+++ b/tests/discrete_tune.py
@@ -1,12 +1,11 @@
 import attune
+import numpy as np
 
 
 def test_discrete():
     dt = attune.DiscreteTune({"hi": (100, 200), "lo": (10, 20), "med": (20, 100)}, default="def")
-    assert dt(150) == "hi"
-    assert dt(20) == "lo"
-    assert dt(15) == "lo"
-    assert dt(100) == "hi"
-    assert dt(70) == "med"
-    assert dt(5) == "def"
-    assert dt(500) == "def"
+    x = [150, 20, 15, 100, 70, 5, 500]
+    y = ["hi", "lo", "lo", "hi", "med", "def", "def"]
+    assert np.all(dt(x) == np.asarray(y))
+    assert dt(20) == dt(np.array(20)) == "lo"  # should choose first valid range
+    assert all([dt(xi).item() == yi for xi, yi in zip(x, y)])
diff --git a/tests/instrument/test_update.py b/tests/instrument/test_update.py
index 06ce880..106c8af 100644
--- a/tests/instrument/test_update.py
+++ b/tests/instrument/test_update.py
@@ -46,7 +46,7 @@ def test_update_existing():
     inst2 = attune.Instrument({"arr": arr_new}, {"tune": attune.Setable("tune")})
     inst_new = attune.update_merge(inst, inst2)
     assert math.isclose(inst_new(0.5)["tune"], 1.5)
-    assert inst_new(0.5)["discrete"] == "med"
+    assert inst_new(0.5)["discrete"] == inst(0.5)["discrete"]
     assert inst_new.transition.type == "update_merge"